Apparatus for forming sheet-metal articles.



J. D. ARTZ.

APPARATUS FOR FORMING SHEET METAL ARTICLES.

APPLICATION FILED MAY HI 19l5.

Patented Dec. 21, 1915.

3 SHEETSSHEET I.

J. D. ARTZ.

APPARATUS FOR FORMING SHEET METAL ARTICLES.

APPLICATION FILED MAY I7. 1915.

Patented D60. 21,1915.

3 SHEETS-SHEET 2.

0 Tami M1 llll FOLUMHIA I'LANUKJIAI'II cu, WAsnmuTON, D, c

J. D. ARTZ.

APPARATUS FOR FORMING SHEET METAL ARTICLES.

. APPLICATION FILED MAY I7. 1915. LTMfiW. Patented Dec.21,1915.

3 SHEETS-SHEET 3.

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"ll Hill a 0 a T PAEN'ZT lFFllQhl.

JOHN DUDLEY ARTZ, 0F DAYTON, OHIO.

APPARATUS FOR FORMING- SHEET-METAL ARTICLES.

LftZdJEEQS.

Application filed May 17, 1915.

T 0 all whom it may concern Be it known that 1, JOHN DUDLEY An'rz,citizen of the United States, residing at Dayton, in the county ofMontgomery and State of @hio, have invented certain new and usefulImprovements in Apparatus for Forming Sheet-Metal Articles, of which thefollowing is a specification.

My invention relates to an improved apparatus for forming sheet metalarticles.

The object of the invention is to simplify the structure as well as themeans and mode of operation of such apparatus whereby it will not onlybe cheapened in construction, but will be more eiiicient in use, capableof being easily and quickly operated, economical in operation, andunlikely to get out of repair.

A further object of the invention is to produce an improved means forforming sheet metal articles or giving to bodies of sheet metal orsimilar material a predetermined contour without the use of a die.

lVith the above primary and other incidental objects in view, as willmore fully appear in the specification, the invention consists of thefeatures of construction, the parts and combinations thereof, or theirequivalents, as hereinafter described and set forth in the claims.

Referring to the drawings, Figure 1 is a side elevation of the assembledapparatus forming the subject matter hereof in its prefer ed form forputting into efiect the herein described method. Fig. 2 is an endelevation thereof. Fig. 3 is a plan view thereof. Fig. 4 is a detailview of the grip per jaws and the connection of the adjustment screw.Fig. 5 is a modification of the gripper adjustment means. Figs. 6 and 7are elevations of elementary apparatus for putting into effect themethod herein de scribed. I

Like parts are indicated by similar characters of reference throughoutthe several views.

lileretofore in forming various articles from sheet metal it has beencustomary to employ in conjunction with the punch or ram which conformsto the interior shape of the article, a die or matrix conforming to theexterior contour thereof. In the forming operation as commonly practisedit is the custom to press or stamp the material into the die or matrixby projecting the punch or ram thereinto upon the inter? Specificationof Letters Patent.

Patented Dec. 211, 1915.

Serial No. 28,736.

posed sheet of material. The making of punches and dies for the methodheretofore employed is a highly skilled art and dies for sheet metalarticles of comparatlvely large size are exceedingly expensive.

The apparatus herein described is especially adapted for formingcomparatively large bodies such as. automobile tonneaux, hoods, fenders,and similar parts such as are usually constructed from sheet metal,without the use of die or matrix.

The operating parts of the preferred form of apparatus are located upona bed comprising parallel girders or I beams 1, 1 connected in spacedrelation one with the other by intermediate transverse connecting rodsand spacers 2, 2. Supported upon the bed girders 1, l is a hydraulicpress of ordinary construction comprising a cylinder or chamber 3 withinwhich reciprocates a stem or plunger carrying at its upper end a head ortable a. Inasmuch as hydraulic presses are in common use and theparticular press employed in this construction may be of any convenientproportion or desired construction, it has not been illustrated indetail. The head or table 4: of the press is guided in its reciprocatorymovement by suitable guides 5 projecting forward from the bed girders 1.At its opposite sides the head 4 is provided with ears or lugs 6 inwhich are rigidly secured parallel pendant shafts 7 carrying at theirlower ends adjustable nuts 8. Attached to the upper sides of the bedgirders 1, 1 at opposite sides of the hydraulic press are ways or guides9 of any suitable form but which in the drawings have been shown in theform of short lengths of girders or beams. Resting upon these ways orguides 9 and slidingly movable thereon are transversely arranged gripperjaw frames 10. These gripper jaw frames are provided on their uppersides with longitudinally disposed grooves or recesses at one side ofwhich is located a stationary gripper jaw or bar 11 preferably, thoughnot necessarily, corrugated and at the opposite side is an oscillatoryjaw 12 preferably, though not necessarily, eccentrically shaped inrelation with its axis of oscillation co-acting with the stationary jaw11 to firmly hold a section of sheet metal inserted between said jaws.The movable or oscillatory jaw is controlled. by means of a hand lever13 and the construction and arrangement of the jaws l1 and 12 is suchthat as the oscillatcry jaw swings upward it tends to approach thestationary jaw whereby the pull or strain exerted upon the jaws by theengaged sheet metal during the forming operation tends to set the jawsto grip the ma terial more tightly. On account of the great strain towhich the gripper jaw frames are subjected, the frames are preferablyreinforced by means of exterior ribs 14. The jaw frames 10 are providedwith hearing faces or lugs 15 on their under sides which engage andslide upon the guides or ways 9. Extending downward from each of thegripper jaw frames 10 are one or more pendant shafts 16 carrying attheir lower ends transverse ties or bars 17 engaging the under sides ofthe bed girders 1. The cross ties 17 are preferably, though notnecessarily, provided with bearing blocks 18 slightly convex on theirengaging faces which bear upon the under sides of the bed girders. Thependant shafts 16 are provided with nuts 19 at their lower ends by whichthe cross ties 17 are supported. The gripper jaw frames 10 with theirconnected pendant shaft 16 and cross head 17 are each independentlyadjustable in relation one with the other and in relation with the hydraulic press. Not only are the gripper jaws capable of independentadjustment but either end of the gripper jaw frames may be adjustedindependently, thereby varying the degree of inclination of the gripperjaw frames one with the other and with the bed girders. In suchadjustment of the gripper jaw frames it is to be understood that theframe 10 with the pendant shaft 16 and cross ties 17 move in unison as asingle unit. As the purpose of the cross ties 17 with their hearingblocks 18 engaging the under edges of the bed girders 1, 1 is to resistthe upward pull or tension of the gripper jaw frames under the influenceof the hydraulic press, it is obvious that chains or cables might besubstituted for the pendant shafts 16 without changing the operation ofthe parts. Such variation is so obvious as not to require illustrationas it will be readily understood by any person skilled in the art towhich this invention pertains. Projecting from the opposite ends'of thegripper jaw frames 10 are hubs or sleeves 20 within which are mountedswivel heads comprising an oscillatory head or body 21 rotating on ahorizontal axis alined with that of the gripper jaw frames and a secondhead or nut 22 journaled in the first mentioned head and oscillating onan axis substantially perpendicular to that of the head 21. The head 21is preferably split or formed in halves to permit the engagement thereinof the oscillatory nuts or heads 22. The oscillatory nuts or heads arescrew threaded for the engagement of the revoluble screw shafts 23. Attheir inner ends the screw shafts 23 are journaled in clevises 2-1pivoted at 25 to ears or lugs projecting from a collar or sleeve 26loosely mounted upon the pendant shaft 7. Intel-posed between the nuts 8and the sleeve or collar 26 is a filler or take up block 27. It is to beunderstood that there is a screw shaft for each end of each gripper jawframe. By the revoluble adjustment of the screw shafts 23 the oppositeends of the gripper jaw frames 10 are independently adjusted whereby thegripper jaw frames may be made to approach or reccde one from the otherand their angularity one with the other and with the bed of theapparatus may be varied.

In the operation of the apparatus a forining head or ram 28 is mountedon the head or table at of the hydraulic press. This forming head or ram28 may be of metal but is preferably of wood, being constructed of heavytimbers or of laminated construction. with metal reinforcements atpoints where necessary. A section of sheet metal or other materialoperated upon is extended across V and about the ram or forming head 28and the opposite ends of the metal section are engaged in the gripperjaw 11 and 12 at the opposite sides of the hydraulic press. It will beunderstood that the gripper frames 10 are first adjusted by means of thescrew shafts 23 substantially into alinenicnt with the sides of the ramhead 28. The actuating medium is then admitted to the chamber 3 and thetable 4t and ram head are forced upward against the section. of sheetmetal, the opposite sides of which are held by the gripper jaws, thusplacing the metal under tension. The pressure of the ram head isgradually increased until, in the formation of automobile tonneaux andsimilar products, a pressure of approximately one hundred and fifty tonsis attained. It will be understood that the mavimum pressure necessaryto affect the material will depend upon the nature, the strength and thegage of the material operated upon. The extreme pressure upon the medialportion of the section of sheet metal while the opposite sides thereofare firmly hold causes the sheet to be stretched into conformity withthe form or ram head. The degree of stretching will vary in differentportions of the sheet in accordance with the contour of the form.

As the table 4: and ram head 28 approach the limit of their stroke theelevation of the pendant shafts 7 in unison therewith causes the filleror take up blocks 27 to engage the sleeves 26 and thereafter carry saidsleeves 26 upward in unison with the movement of the table 4: and theram head 28. As before described, this sleeve 26 forms a part of thetoggle link formed by the screw shaft 23 connecting the gripper jawframe. As the sleeve 26 is. drawn upward this toggle link operates tocause the gripper jaw frames 10 to automatically approach one toward theother to draw the material more tightly into contact with the sides ofthe form or ram head 28. This movement of the gripper jaw frames furthertends to increase the tension upon the section of sheet material and todistribute the stress or strain.

lit will be understood that by employing take up or filler blocks 27 ofdifi'erent heights and by the adjustment of the nuts 8 the gripper jawframes may be drawn inward earlier or later during the time of operationof the ram head. By this means the sheet material is placed under a highdegree of tension unequally distributed whereby some portion of thesheet material will be stretched to a further degree than others,causing it to correspondin ly change its shape to conform to that of thehead or ram 28.

To insure the conformity of the sheet material to the form or head andto facilitate the stretching or flow of the metal, the material operatedupon may be hammered or swaged during the stretching operation. Likewisein forming automobile parts the margins of the sheet material arepreferably flanged by hammering while the material is stretched over theform or ram head.

While in Figs. 1 to linclusive each of the screw shafts 23 isindependent of the other screw shafts, whereby each of the screw shaftsmay be rotated independently to adjust the corresponding end of thegripper jaw frame, in Fig. 5 there is shown a modification in which thecorresponding ends of the opposite gripper jaw frames are connected onewith the other by a single screw shaft provided with right and left handthreads by the rotation of which the gripper jaw frames are caused tosimultaneously approach one toward the other. It is obvious that inemploying this construction the automatic contraction or inward movementof the gripper jaw frames under the influence of the toggle links beforementioned is dispensed with.

While the form of apparatus hereinbefore described is preferred anelementary form or modification of the apparatus is shown in Figs. 6 and7. Referring to Fig. 6, thereis shown a screw press comprising a base 29having uprights 30 supporting transverse or head girders 31. Supportedupon the head girders 31 in any suitable manner is a main pressure scr w32 hearing at its lower end upon a head or form 33 about which. thearticle is to be shaped. Located on opposite sides of the head or form33 are pedestals or supports 34- with the heads of which clamp plates 35cotiperate to firmly hold the opposite sides of the section 36 of sheetmetal. The clamp plates 35 are forced down ward upon the heads of thepedestals or supports 34: to engage the metal section by means ofclamping screws 37. The sections 36 of sheet metal, having been engagedby the clamping plates 35 over the tops of the pedestal 3%, forms asling or bight in which the form or head 33 rests. Pressure is thenapplied by means of the main pressure screw 32 to force the head or formdownward into the bight and thereby stretch the sheet material intoconformity therewith. An apparatus similar to that shown in Fig. (5 hasbeen successfully employed in carrying out the herein described methodprior to the development of the preferred form of apparatus hereinbefore described.

In Fig. 7 there is shown a modification of the apparatus shown in Fig.6. In this construction the head or form is stationariiy supported uponthe base 29. The section 36 of material to be operated upon extendsacross the top of the form or head and its opposite sides are clamped insuitable clamps or jaws 38 carried by pressure screws 39 engaged withthe head girders 31. By the adjustment of the pressure screw 39 thesheet metal section 36 is set or tensioned over the form or head 33 byforcing the clamping bars or jaws 38 downward and carrying the oppositesides or ends of the section of sheet metal therewith.

From the above description it will be apparent that there is thusprovided a device of the character described possessing the particularfeatures of advantage before enumerated as desirable but which obviouslyis susceptible of modification in its form, proportion, detailconstruction, or arrangement of parts without departing from the principle involved or sacrificing any of its advan tages.

While in order to comply with the statute the invention has beendescribed in language more or less specific as to certain structuralfeatures, it is to be understood that the invention is not limited toany specific details but that the means herein described comprise butone mode of putting the invention into effect and the invention istherefore claimed broadly in any of its possible forms or modificationswithin the scope of the appended claims.

Having thus described my invention, I claim:

1. In a sheet metal forming apparatus, a

contoured form corresponding with the interior of the article to beproduced, independent holding means located on opposite sides of theform adapted to independently engage the opposite sides of a section ofma terial extending across the contoured form, and means for relativelymoving the holding means and form to stretch the material intoconformity with the contoured form.

2. In a sheet metal forming apparatus, independent means for firmlyholding the op posite edges of the sheet of material to be operatedupon, a contoured head substan tially corresponding with the interior ofthe article to be produced engaging the sheet of material between theholding means, and means for placing the sheet of material under tensionto stretch the material thereof substantially into conformity with thecontour of the head.

3. In a sheet metal forming apparatus, a contoured head substantiallycorresponding with the inteior of the article to be produced, separategrippers located on opposite sides of the contoured head adapted tofirmly secure the opposite sides of a sheet of material extending acrossthe contoured head, and means for relatively moving the grippers andhead to place the sheet material under tension to stretch the sheetmaterial substantially into conformity with the head.

4. In a sheet metal forming apparatus, a reciprocatory ram, separategrippers located on opposite sides of the ram and engaging opposite endsof a sheet of metal, a contoured head carried by the ram, and means toreciprocate the ram to stretch a sheet of metal extending between thegrippers substantially into conformity with the contoured head.

5. In a sheet metal forming apparatus, a contoured forming head,laterally movable gripper members located on opposite sides of the headand adapted to engage the pposite sides of a section of materialextending across the head, and means to move the gripper members to andfrom each other, substantially as specified.

6. In a sheet metal forming apparatus, a contoured forming head, grippermembers located on opposite sides of the head and adapted to engage theopposite sides of a section of material extending acrossthe head, andmeans to move the gripper members to different angular positions inrelation one with the other.

7. In a sheet metal forming apparatus, a contoured head, laterallymovable gripper members located on opposite sides of the head andadapted to engage opposite sides of a section of material extendingacross the head, and means to independently adjust the opposite ends ofthe gripper members laterally to and from the head.

8. In a sheet metal forming apparatus, a contoured head, laterallymovable gripper members located on opposite sides of the head andadapted to engage opposite sides of a section of material extendingacross the head, and means to independently adjust the said grippermembers later lly to and from the head.

9. In a sheet metal forming apparatus, a reciprocatory forming ram,laterally movable gripper members located at opposite sides of the ramadapted to engage opposite sides of a section of material extendingacross the ram, and means for causing the grippers to move laterally onetoward the other in unison with the movement of the ram.

10. In a sheet metal forming apparatus, a reciprocatory forming ram,laterally movable gripper members located at opposite sides of the ramadapted to engage opposite sides of a section of material extendingacross the ram, and an operative connection between the ram and gripperswhereby the ram is permitted an initial movement independent of thegrippers and upon further movement of the rain the grippers will bemoved laterally in unison therewith.

11. In a sneet metal forming ilDllili'ilidlS, a reciprocatory formingrain, gripper members located at opposite sides oi the ram adapted toengage opposite sides of a section of material extending across therain, and means for moving the gripper members at substantially rightangles to the direction or" movement of the ram simultaneouslytherewith.

12. In a sheet metal forming apparains, a forming head, gripper memberslocated on opposite sides of the head and adapted to engage a sheet ofmaterial extending across the head, swivel heads 011 opposite ends ofthe gripper members, and adjusting elements.

connected with the swivel heads whereby the gripper members andadjusting elements may assume dili'erent angular positions in relationone with the other.

In a sheetmetal forming apparatus, a rcciprocatory ram, laterally mocable gripper members located on opposite sides of the ram, and togglelinlzs connecting the gripper members one with the other and operated byLllG movement of the ram to cause said gripper members to morealternately to and from each other.

ll. In a sheet metal forming apparatus, a reciprocatory ram, laterallymovable gripper members located on opposite sides of tie ram, togglelinks connected with the pp er members, a head slidingly cormected Mhhthe ram to which the toggle links are attached, and adjustable meanscarried by the ram-for engaging the sliding head and moving same inunison therewith.

15. In a sheet metal forming apparatus, a reciprocatory ram, laterallymovable gripper nembers located on opposite sides of the and adjustabletoggle connections becn the gripper members and the ram.

16. In a sheet metal forming apparatus, a reciprocatory ram, laterallymovable gripnen'ibers located on opposite sides of ne ram, adjustmentscrews engaging the ppers and attached to the ram whereby we grippersare capable of lateral adjust ment independent of the rain but are movedin unison therewith, substantially as specilied.

17. In sheet metal forming apparatus, a reciprocatory ram, laterallymovable grippers for the material operated upon and actuatingconnections between the grippers and the ram whereby said grippers willbe automatically shifted laterally in unison with the longitudinalmovement of the ram.

18. In a sheet metal forming apparatus, a reciprocatory ram, laterallymovable grippers for the material operated upon actuated by the movementof the ram, and means to adjust said grippers laterally independent ofthe ram.

19. In a sheet metal forming apparatus, a reciprocatory ram, laterallymovable grippers for the material operated upon and an actuatingconnection between the grippers and the ram, and means for initiallymoving the ram independent of the grippers and thereafter moving thegrippers laterally in unison with the further movement of the ram.

20. In an apparatus for forming articles from sheet material without theuse of a matrix comprising a forming head conforming to the interior ofthe article to be formed across which the material operated upon isextended, holding means for the marginal portions of the sheet material,and means for producing an operative movement of the holding means andforming head in relation one with the other to stretch the sheetmaterial into conformity with said head.

21. In an apparatus for forming articles from sheet material without theuse of a matrix comprising a forming head conforming to the interior ofthe article to be formed across which the material operated upon isextended, holding means for the marginal portions of the sheet materialclosed and opened to engage and release the material operated uponindependent of the relative movement of the head and holding means, andmeans for producing an operative movement of said head. and holdingmeans in relation one with the other to stretch the material intoconformity with the forming head.

22. In an apparatus for forming articles from sheet material without theuse of a matrix comprising a forming head conforming to the interior ofthe article to be formed across which the material operated upon isextended, holding means for the marginal portions of the sheet material,means for shifting said holding means laterally while engaged with thematerial, and means for producing an operative movement of the holdingmeans and forming head in relation one with the other to stretch thematerial into conformity with the head.

23. In an apparatus for forming articles from sheet material without theuse of a matrix comprising a forming head conforming to the interior ofthe article to be formed across which the material operated upon isextended, holding means for the marginal portions of the sheet material,and means for automatically shifting the holding means laterally by arelative movement of the head and holding means, and means to producesuch relative movement to stretch the material into conformity with thehead.

24. In an apparatus for forming articles from sheet material without theuse of a matrix comprising a forming head conforming to the interior ofthe article to be formed across which the material operated upon isextended, holding means for the marginal portions of the sheet material,and means for shifting the holding means laterally independent of theoperative movement of the head and holding means in relation one withthe other.

525. In an apparatus for forming articles from sheet material withoutthe use of a matrix comprising a forming head conforming to the interiorof the article to be formed across which the material operated upon isextended, holding means for the marginal portions of the sheet material,means for producing an initial operative movement of the head andholding means in relation one with the other independent of any lateralmovement of the holding means, and to subsequently move the holdingmeans laterally in unison with the relative movement of the head andholding means.

In testimony whereof, I have hereunto set my hand this 4th day of May A.D. 1915.

JOHN DUDLEY ARTZ.

Witnesses:

HARRY F. NOLAN, CARRIE M. RECKER.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. C.

